Metal-decorated Tri-graphene as a high-performance reversible hydrogen storage medium: A first-principles study

Hydrogen is a promising candidate for renewable energy storage and transportation due to its high energy density and zero carbon emissions. Its practical applications face challenges related to safe, efficient storage and release systems. This review article investigates advanced nanostructured materials for hydrogen storage, including metal acetylide and cyanide complexes, B,N-doped γ-graphyne nanotubes (γ-GNT), lithium-phosphide double helices, and Ni-decorated carbon-based clusters. Density Functional Theory (DFT) based computations are used to analyze binding energies, thermodynamic stability, and adsorption mechanisms. Ni-decorated C12N12 nanoclusters demonstrate enhanced storage capacities, binding up to eight H2 molecules with a favorable N-(μ-Ni)-N configuration. Lithium-phosphide double helices show potential for 9.6 wt% hydrogen storage within a stable, semiconducting framework. Functionalization of γ-GNT with OLi2 at boron-doped sites significantly enhances storage potential, achieving optimal hydrogen binding energies for practical applications. Additionally, metal acetylide and cyanide complexes, stabilized by noble gas insertion, display thermodynamically favorable hydrogen adsorption. These results highlight the potential of these functionalized nanostructures for achieving high-capacity, reversible hydrogen storage. The nanostructures in this study, such as γ-graphyne nanotubes (γ-GNT), lithium-phosphide double helices, metal acetylide and cyanide complexes, and Ni-decorated carbon-based clusters, are selected based on their ability to exhibit complementary hydrogen adsorption mechanisms, including physisorption and chemisorption. γ-GNT offers high surface area and tunable electronic properties, ideal for physisorption enhanced by heteroatom doping. Lithium-phosphide double helices facilitate Kubas-like chemisorption through unsaturated lithium centers. Metal acetylide and cyanide complexes stabilize hydrogen adsorption via charge transfer and conjugated frameworks, while Ni-decorated clusters combine polarization-induced physisorption. These materials represent a strategic approach to addressing the challenges of hydrogen storage through diverse and synergistic mechanisms. The review also addresses challenges and outlines future directions to advance hydrogen's role as a sustainable fuel.

Hydrogen has been regarded as a promising alternative to traditional fossil fuels, presenting itself as a viable and environmentally friendly energy choice. The design and fabrication of highly efficient hydrogen storage materials is crucial to the wide utilization of hydrogen-based technologies. Magnesium-based nanocrystalline materials have received significant interest in the field of hydrogen storage due to their remarkable hydrogen storage capabilities and release efficiency. This review emphasizes on the most useful techniques including vapor deposition, sol-gel synthesis, electrochemical deposition, magnetron sputtering, and template-assisted approaches used for the fabrication of Magnesium-based nanocrystalline hydrogen storage materials (Mg-NHSMs), stressing their advantages, limitations, and recent advancements. These cutting-edge techniques demonstrate their significance in offering useful insights into the performance of Mg-NHSMs. Further, this review describes various applications of Mg-NHSMs. In addition, this review highlights the conclusion and future perspectives on the improvement of magnesium based nanocrystalline materials for efficient hydrogen storage.

Energy is regarded as a key resource that may encourage numerous companies to expand and flourish given the rapid advancement of technology. However, due to the contamination of the usage of traditional fossil fuels, deploying new and clean energy resources is the concentrated solution. New energy sources such as wind energy and solar energy are constantly being developed. In addition, three methods exist for storing hydrogen that is a typical clean energy source, including compressed gas storage, cryogenic liquid gas storage, and hydrogen storage materials via adsorption and desorption. As a result, hydrogen storage is receiving more and more attention, and different hydrogen storage materials have been developed. This research will introduce the application of four different types of porous materials in the field of hydrogen storage, including zeolites, activated carbons (AC), carbon nanotubes (CNTs), and metal-organic frameworks (MOFs). Hydrogen can be successfully adsorbed on these materials to varying degrees through chemisorption and physisorption. For improving the hydrogen storage capability (HSC), synthetic strategies such as doping metal elements and synthesizing composite porous materials were designed and used to enhance the hydrogen storage properties of the materials. In the future, satisfying the U.S. Department of Energy (DOE) target would stimulate more and more great-performing porous materials to be synthesized, which can provide a new idea for new hydrogen storage technologies.

Recent advancement in metal-organic frameworks for hydrogen storage: Mechanisms, influencing factors and enhancement strategies

Recent advances in metastable alloys for hydrogen storage: a review

The shift from fossil fuels to renewable energy sourcesis essentialfor reducing global carbon emissions and addressing climate change.Developing advanced materials for efficient hydrogen storage enablesthe development of sustainable energy solutions in this context. Herein,we propose sodium-decorated TPHE-graphene as a high-performance two-dimensionalmaterial for hydrogen storage. Density functional theory calculationsand molecular dynamics simulations demonstrate that TPHE-grapheneexhibits dynamical, thermal, energetic, and mechanical stability.The monolayer displays metallic behavior and a high Young’smodulus of 250.46 N/m. Upon sodium decoration, strong chemisorptionoccurs with a binding energy of −2.08 eV and minimal tendencyfor Na atom clustering. Hydrogen adsorption analysis reveals thateach Na atom can bind up to five H2 molecules, resultingin a gravimetric storage capacity of 9.52 wt %. The calculated H2 adsorption energies range from −0.22 to −0.18eV, falling within the ideal range for reversible adsorption underambient conditions. These findings highlight Na-decorated TPHE-grapheneas a structurally robust and efficient hydrogen storage material well-suitedfor future green energy applications.

First principle studies on triphenylene-hexathiol-based metal-organic framework for hydrogen storage application

Structural and hydrogen storage properties of melt-spun Mg–Ni–Y alloys

It is a consensus that the hydrogen economy has come to a standstill due to the lack of feasible hydrogen storage solutions, especially, the suitable hydrogen storage materials. In this work, the potential of a new kind of two-dimensional (2D) AXenes, Na2N and K2N, as hydrogen storage materials are evaluated by the first-principles calculations. In particular, we find that Na2N in T phase indicates a hydrogen storage capacity as high as 6.25 wt% with a desirable hydrogen adsorption energy of –0.167 eV per H2 molecule and a desorption temperature of 216 K, identifying T-phase Na2N to be a very promising reversible hydrogen storage material. In accordance to our results, H2–Na2N interaction causes H2 charge polarization, which is responsible for the moderate binding strength. In addition, Gibbs adsorption free energy reveals that the system will be more stable as more H2 molecules are loaded on the surface.

Responses to comments on the paper “Two-dimensional Sc2C: A reversible and high capacity hydrogen storage material predicted by first-principles calculations”

Part 1 Introduction: Hydrogen storage technologies Hydrogen futures: Emerging technologies for hydrogen storage and transport Hydrogen containment materials Solid-state hydrogen storage system design. Part 2 Analysing hydrogen interactions: Structural characterisation of hydride materials Neutron scattering techniques for analysing solid-state hydrogen storage Reliably measuring hydrogen uptake in storage materials Modelling of carbon-based materials for hydrogen storage. Part 3 Physically bound hydrogen storage: Storage of hydrogen in zeolites Carbon nanostructures for hydrogen storage Metal-organic framework materials for hydrogen storage. Part 4 Chemically bound hydrogen storage: Intermetallics for hydrogen storage Magnesium hydride for hydrogen storage Alanates as hydrogen storage materials Borohydrides as hydrogen storage materials Imides and amides as hydrogen storage materials Multicomponent hydrogen storage systems Organic liquid carriers for hydrogen storage Indirect hydrogen storage in metal ammines Conclusion: Technological challenges in hydrogen storage.

This document summarizes the status of carbon-neutral hydrogen production, storage and transport, and utilization. The state of the art in the implementation, limitations, and challenges of these technologies are summarized. Sources of hydrogen are broadly categorized as hydrcoarbons or water and the processes used to convert these sources to hydrogen as catalytic, thermochemical, or electrochemical. Catalytic steam methane reforming of methane is the dominant process today. Other processes have smaller production volumes and the technology is less mature, but are being deployed at increasing rates, most notably water electrolyzers for hydrogen fueling stations. Efficient transport and storage of hydrogen is one of the major challenges facing a hydrogen-based energy economy. This arises in part from its low volumetric energy density necessitating very high pressures or cryogenic temperatures to store sufficient amounts for practical applications. High-pressure compressed hydrogen cylinders are the incumbent hydrogen storage technology for applications such as light-duty fuel cell electric vehicles, for example. The storage of hydrogen in materials or in chemicals is being pursued to address the issues associated with compression, such as parasitic energy loss and weight, size, and cost of storage containers. The complex nature of the chemical and physical processes involved in the uptake, storage, and release of hydrogen has slowed the discovery of suitable hydrogen storage materials. Both small and large-scale storage face the challenge of embrittlement of the storage media by hydrogen. There is a myriad of uses of hydrogen offering the promises of improving the efficiency of various applications and reducing or eliminating CO2 emissions. These range from direct electrochemical conversion to electricity to power vehicles and grid-level stationary applications to combustion to production of chemicals and commodities. One of the most impactful applications in terms of reduction of CO2 emissions is fuel cell passenger vehicles and heavy-duty vehicles such as class 8 trucks. The challenges facing widespread deployment of fuel cells, beyond the major hurdle of the lack of a hydrogen distribution infrastructure, are cost and durability, primarily related to the precious metal cathode catalyst and its durability. The other uses of hydrogen from conversion to hydrocarbons, polymer upcycling, and upgrading of bio-oils are at varying stages of maturity and also face fundamental challenges associated with catalytic processes and materials.

The lack of safe, efficient, and economical hydrogen storage technologies is a hindrance to the realization of the hydrogen economy. Reported herein is a reversible formate-based carbon-neutral hydrogen storage system that is established over a novel catalyst comprising palladium nanoparticles supported on nitrogen-doped mesoporous carbon. The support was fabricated by a hard template method and nitridated under a flow of ammonia. Detailed analyses demonstrate that this bicarbonate/formate redox equilibrium is promoted by the cooperative role of the doped nitrogen functionalities and the well-dispersed, electron-enriched palladium nanoparticles.

In an attempt to develop lithium borohydrides as reversible hydrogen storage materials with high hydrogen storage capacities, the feasibility of reducing the dehydrogenation temperature of the lithium borohydride and moderating rehydrogenation conditions was explored. The lithium borohydride was modified by ball milling with metal oxides and metal chlorides as additives. The modified lithium borohydrides released 9 wt % hydrogen starting from 473 K. The dehydrided modified lithium borohydrides absorbed 7-9 wt % hydrogen at 873 K and 7 MPa. The modification with additives reduced the dehydriding starting temperature from 673 to 473 K and moderated the rehydrogenation conditions from 923 K/15 MPa to 873 K/7 MPa. XRD and SEM analysis revealed the formation of an intermediate compound that might play a key role in changing the reaction path, resulting in the lower dehydriding temperature and reversibility. The reversible hydrogen storage capacity of the oxide-modified lithium borohydrides decreased gradually during hydriding/dehydriding cycling. One of the possible reasons for this effect might be the loss of boron during dehydrogenation, but this can be prevented by changing the dehydriding path using appropriate additives. The additives reduced the dehydriding temperature and improved the reversibility, but they also reduced the hydrogen storage capacity. The best compromise can be reached by selecting appropriate additives, optimizing the additive loading, and using new synthesis processes other than ball milling.

Pristine [formula omitted] monolayer as highly efficient reversible hydrogen storage material under ambient temperature and pressure